There have been computer systems that construct virtual space which is a real world reproduced and provide users with the virtual space. There are systems that play a game which generates a virtual world in the virtual space and introduces a so-called avatar representing a person, or simulate a study, analysis or prediction or the like.
In generation of those virtual worlds, virtual space which is a real world reproduced is constructed by the photo-based rendering (image creation) technology that constructs pseudo virtual space by pasting (texture mapping) photographs shot in a real world onto the interior of space containing a user.
As a system using this photo-based rendering technology, there is an exclusive photographing system which efficiently stores a plurality of real shot images sequentially shot at the same time, along with information on the position at which those shots are taken, in an image database system, and reproduces and displays images in real time from an arbitrary position at the time of reproduction to generate a virtual world (see Japanese Unexamined Patent Publication (Kokai) No. H11-168754).
As a technique relating to photo-based rendering, there are a technique of recording a plurality of high-definition images with different gazing directions and a plurality of background images in a recording medium with the gazing directions being search indexes, and, at the time of reproduction, detecting the view direction of an observer and synthesizing the images through image processing (see Japanese Unexamined Patent Publication (Kokai) No. H07-236113), an electro-optic visualization system using positions and postures, and a method of interpolating and generating directional images from a plurality of images acquired from cameras placed in omnidirections (see Japanese Unexamined Patent Publication (Kokai) No. 2002-92597).
As a camera which shoots a real world, there is a digital camera capable of providing a computer with accurate images in the form of digital data. There is a digital camera which has a GPS (Global Positioning System) and an azimuth sensor or a three-dimensional gyro sensor mounted to that digital camera to be able to record a shooting position, a shooting direction and a shooting angle of elevation (see Japanese Unexamined Patent Publication (Kokai) No. 2004-080359).